I have two nodes installed. Node 1 function as controller node, network node and compute node. Node 2 works only as a compute node.

I am using neutron linuxbridge plugin for the networking. Now if a VM is scheduled on Node2, everything's OK. While if a VM is sheduled on Node1, it always fails to get IP from dhcp.

Starting network... udhcpc (v1.18.5) started Sending discover... Sending discover... Sending discover... No lease, failing

It seems dhcp reply cannot reach the target VM.

Here's output of tcpdump

[root@controller 088f3c8d-ecc6-441a-be76-24d00247492b]# tcpdump -i any |grep -i dhcp

tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on any, link-type LINUX_SLL (Linux cooked), capture size 65535 bytes

10:14:15.497874 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:16:3e:f1:96:f3 (oui Unknown), length 280

10:14:15.497890 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:16:3e:f1:96:f3 (oui Unknown), length 280

10:14:15.497894 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:16:3e:f1:96:f3 (oui Unknown), length 280

10:14:15.497898 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:16:3e:f1:96:f3 (oui Unknown), length 280 10:14:15.497901 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:16:3e:f1:96:f3 (oui Unknown), length 280

10:14:15.497874 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:16:3e:f1:96:f3 (oui Unknown), length 280

10:14:15.498994 IP 10.147.1.3.bootps > 10.147.1.4.bootpc: BOOTP/DHCP, Reply, length 325

10:14:15.498998 IP 10.147.1.3.bootps > 10.147.1.4.bootpc: BOOTP/DHCP, Reply, length 325

10:14:18.503070 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:16:3e:f1:96:f3 (oui Unknown), length 280

10:14:18.503083 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:16:3e:f1:96:f3 (oui Unknown), length 280

10:14:18.503087 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:16:3e:f1:96:f3 (oui Unknown), length 280

10:14:18.503091 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:16:3e:f1:96:f3 (oui Unknown), length 280

10:14:18.503094 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from fa:16:3e:f1:96:f3 (oui Unknown), length 280 10:14:18.503070 IP 0.0.0.0.bootpc > 255.255.255.255.bootps: BOOTP/DHCP, Request from ... (more)